Request a `Find` mode (or `name_pattern` arg on `Directory` mode)

[iamDyeus]

# What would be ideal:
fs_read(".", mode="Find", pattern="*auth*")
# Returns: {"type": "find", "matches": [{"path": "src/auth/login.ts"}, ...]}

This would let find_files be fully native with zero Python filtering. The Directory + Python glob interim works correctly but depth=10 means contextinator walks the whole tree upfront even if only 2 files match — a native Find mode would be more efficient.